dale (n.)

level or gently sloping ground between low hills with a stream flowing through it, Old English dæl "vale, valley, gorge," from Proto-Germanic *dalaz "valley" (source also of Old Saxon, Dutch, Gothic dal, Old Norse dalr, Old High German tal, German Tal "valley"), perhaps from PIE *dhel- "a hollow" (source also of Old Church Slavonic dolu "pit," Russian dolu "valley"), or perhaps a substratum word. It was preserved by Norse influence in the north of England. Related: Dalesman.